Macrofauna associated to a semi-intensive Litopenaeus vannamei (Boone, 1931) culture system at the Patos Lagoon estuary (southern Brazil) Macrofauna associada a um cultivo semi-intensivo de Litopenaeus vannamei (Boone, 1931) no estuário da Lagoa dos Patos (sul do Brasil)

The macrofauna community structure at two distinct environments (e.g., a pond and a sedimentation basin) of a shrimp farm was compared to the natural environment across an entire cycle of Litopenaeus vannamei culture located at estuarine region of the Patos Lagoon, southern Brazil. Both farm habitats showed lower values of number of species and density (pond: 1spp. and 8 ind./0.008m2; sedimentary basin: 3spp. and 12 ind./0.008m2) compared to natural environment (6spp. and 40 ind./0.008m2). However, the biomass values at sedimentary basin (mean = 0.06 g/0.008m2) were twice higher than natural environment. The absent of previous pond preparation for biota growth stimulation associated to negative effects of own shrimps on the macrofauna result in the low diversity and abundance observed at the pond. Otherwise, the presence of a biota relatively abundant and with high biomass at sedimentary basin could to contribute to increase effluent quality of the shrimp farm. The macrofauna community structure at two distinct environments (i.e., a pond and a sedimentation basin) of a shrimp farm was compared to the natural environment across entire cycle of Litopenaeus vannamei culture located at estuarine region of the Patos Lagoon, southern Brazil. Both farm habitats showed lower values of number of species and density (pond: 1spp. and 8 ind./0.008m2; sedimentary basin: 3spp. and 12 ind./0.008m2) compared to natural environment (6spp. and 40 ind./0.008m2). However, the biomass values at sedimentary basin (mean = 0.06 g/0.008m2) were twice higher than natural environment. At pond, low richness of macrofauna seems related to absence of previous pond preparation; while shrimp predation and/or disturbance resulting in low densities after begin of culture. Otherwise, the presence of a biota relatively abundant and with high biomass at sedimentary basin could contribute to increase effluent quality of the shrimp farm.